【初次学习、配置的笔记，如有不当，欢迎在评论区纠正 -- 萌狼蓝天 @ 2021-12-02】
基本概念
FTP访问方式
- 实体账号：本地账户
- 来宾账户：guest
- 匿名登录：anonymous fp
实训
环境搭建
安装FTP软件包
查询是否已安装FTP软件包 vsftpd
rpm -q vsftpd
查询vsftpd软件包的信息
yum info vsftpd
安装FTP软件包vsftpd
yum install vsftpd
关于错误代码256
[Errno 256] No more mirrors to try.
问题分析：我挂载的本地镜像，所以：应当在每次开机后重新挂载，才能使用的
问题解决方案：重新挂载了本地镜像，就可以成功下载了
安装FTP客户端lftp
查询是否已安装lftp
rpm -q lftp
安装lftp
yum install lftp
修改FTP配置文件
配置文件所在位置 /etc/vsftpd/vsftpd.conf
vim /etc/vsftpd/vsftpd.conf
备份原来的配置文件
cd /etc/vsftpd/
ls
cp vsftpd.conf vsftpd.conf.bak
ls
修改配置文件
vim vsftpd.conf
（1）允许匿名用户登陆，并设置匿名用户登陆路径
anonymous_enable=YES
anon_root=/var/ftp/pub
（2）是否允许用户有写入权限
（3）设置用户的umask码为022
（创建目录权限为755rwxr-xr-x,创建文件权限为644）
（4）匿名用户操作权限设置
上传文件权限为yes；新建文件夹权限为yes；匿名用户其他写权限为yes；匿名用户下载不具备读权限的文件为no；
（5）其他设置
完整文件内容如下：
# Example config file /etc/vsftpd/vsftpd.conf
#
# The default compiled in settings are fairly paranoid. This sample file
# loosens things up a bit, to make the ftp daemon more usable.
# Please see vsftpd.conf.5 for all compiled in defaults.
#
# READ THIS: This example file is NOT an exhaustive list of vsftpd options.
# Please read the vsftpd.conf.5 manual page to get a full idea of vsftpd's
# capabilities.
#
# Allow anonymous FTP? (Beware - allowed by default if you comment this out).
anonymous_enable=YES
#
# Uncomment this to allow local users to log in.
# When SELinux is enforcing check for SE bool ftp_home_dir
local_enable=YES
#
# Uncomment this to enable any form of FTP write command.
write_enable=YES
#
# Default umask for local users is 077. You may wish to change this to 022,
# if your users expect that (022 is used by most other ftpd's)
local_umask=022
#
# Uncomment this to allow the anonymous FTP user to upload files. This only
# has an effect if the above global write enable is activated. Also, you will
# obviously need to create a directory writable by the FTP user.
# When SELinux is enforcing check for SE bool allow_ftpd_anon_write, allow_ftpd_full_access
anon_upload_enable=YES
anon_root=/var/ftp/pub
anon_mkdir_write_enable=YES
anon_other_write_enable=YES
anon_world_readable_only=NO
#
# Uncomment this if you want the anonymous FTP user to be able to create
# new directories.
anon_mkdir_write_enable=YES
#
# Activate directory messages - messages given to remote users when they
# go into a certain directory.
dirmessage_enable=YES
#
# Activate logging of uploads/downloads.
xferlog_enable=YES
#
# Make sure PORT transfer connections originate from port 20 (ftp-data).
connect_from_port_20=YES
#
# If you want, you can arrange for uploaded anonymous files to be owned by
# a different user. Note! Using "root" for uploaded files is not
# recommended!
#chown_uploads=YES
#chown_username=whoever
#
# You may override where the log file goes if you like. The default is shown
# below.
#xferlog_file=/var/log/xferlog
#
# If you want, you can have your log file in standard ftpd xferlog format.
# Note that the default log file location is /var/log/xferlog in this case.
xferlog_std_format=YES
#
# You may change the default value for timing out an idle session.
#idle_session_timeout=600
#
# You may change the default value for timing out a data connection.
#data_connection_timeout=120
#
# It is recommended that you define on your system a unique user which the
# ftp server can use as a totally isolated and unprivileged user.
#nopriv_user=ftpsecure
#
# Enable this and the server will recognise asynchronous ABOR requests. Not
# recommended for security (the code is non-trivial). Not enabling it,
# however, may confuse older FTP clients.
#async_abor_enable=YES
#
# By default the server will pretend to allow ASCII mode but in fact ignore
# the request. Turn on the below options to have the server actually do ASCII
# mangling on files when in ASCII mode. The vsftpd.conf(5) man page explains
# the behaviour when these options are disabled.
# Beware that on some FTP servers, ASCII support allows a denial of service
# attack (DoS) via the command "SIZE /big/file" in ASCII mode. vsftpd
# predicted this attack and has always been safe, reporting the size of the
# raw file.
# ASCII mangling is a horrible feature of the protocol.
#ascii_upload_enable=YES
#ascii_download_enable=YES
#
# You may fully customise the login banner string:
#ftpd_banner=Welcome to blah FTP service.
#
# You may specify a file of disallowed anonymous e-mail addresses. Apparently
# useful for combatting certain DoS attacks.
#deny_email_enable=YES
# (default follows)
#banned_email_file=/etc/vsftpd/banned_emails
#
# You may specify an explicit list of local users to chroot() to their home
# directory. If chroot_local_user is YES, then this list becomes a list of
# users to NOT chroot().
# (Warning! chroot'ing can be very dangerous. If using chroot, make sure that
# the user does not have write access to the top level directory within the
# chroot)
#chroot_local_user=YES
#chroot_list_enable=YES
# (default follows)
#chroot_list_file=/etc/vsftpd/chroot_list
#
# You may activate the "-R" option to the builtin ls. This is disabled by
# default to avoid remote users being able to cause excessive I/O on large
# sites. However, some broken FTP clients such as "ncftp" and "mirror" assume
# the presence of the "-R" option, so there is a strong case for enabling it.
#ls_recurse_enable=YES
#
# When "listen" directive is enabled, vsftpd runs in standalone mode and
# listens on IPv4 sockets. This directive cannot be used in conjunction
# with the listen_ipv6 directive.
listen=NO
#
# This directive enables listening on IPv6 sockets. By default, listening
# on the IPv6 "any" address (::) will accept connections from both IPv6
# and IPv4 clients. It is not necessary to listen on *both* IPv4 and IPv6
# sockets. If you want that (perhaps because you want to listen on specific
# addresses) then you must run two copies of vsftpd with two configuration
# files.
# Make sure, that one of the listen options is commented !!
listen_ipv6=YES
pam_service_name=vsftpd
userlist_enable=YES
tcp_wrappers=YES
设置匿名用户访问目录
设置匿名用户访问目录/var/ftp/pub，该目录权限必须设置为755，
在该目录下新建文件test_XXX_01和目录test_XXX_dir，在文件test_XXX_01中随意输入若干内容；
将该文件和目录权限设置为777；
关闭防火墙并重启ftp服务器
systemctl stop firewalld
systemctl restart vsftpd.service
# 设置开机启动
systemctl enable vsftpd.service
可能遇见的错误
配置文件有误，检查输入或者修改的地方有没有多余的空格
解决方案
在ftp客户端，采用lftp软件访问ftp服务器
开启另外一台机器，切换到root身份安装lftp
使用ftp远程连接
下载文件到本地
尝试在test_zwj_dir中新建目录并上传文件
创建目录失败，解决方案如下:
在ftp服务端修改配置文件 vim /etc/selinux/config修改内容如下：
将SELINUX的值由enforcing修改为disabled
# This file controls the state of SELinux on the system.
# SELINUX= can take one of these three values:
# enforcing - SELinux security policy is enforced.
# permissive - SELinux prints warnings instead of enforcing.
# disabled - No SELinux policy is loaded.
SELINUX=disabled
# SELINUXTYPE= can take one of three values:
# targeted - Targeted processes are protected,
# minimum - Modification of targeted policy. Only selected processes are protected.
# mls - Multi Level Security protection.
SELINUXTYPE=targeted
重启服务 systemctl restart vsftpd.service
重启主机
开机后记得关闭防火墙，重启vsftp